Is 8GB recommended now with the -Xms5G -Xmx5G settings?
Where does the garbage collector line go, same as above?

Generally the more RAM the supernode has, the better it is. Also, with 8GB and more the G1 garbage collector should be preferred, else the “stop the world” events for garbage collection tend to take too long.
The above settings are the standard settings,

-Xms5G -Xmx5G -XX:+UseG1GC -XX:MaxGCPauseMillis=200

i use them for the 8GB nodes i have, they work well.
4GB might still work, but you have to restart NIS every now and then.

Any idea why chain height is stuck on 20133303? I have been experimenting with different xms xmx settings due to previous computing power failures. I lowered to 2500 initially same issue. Then tried different settings until 2048. Which fixed computing power, but failed height. I tried 2100, 2200, 2300. Recently been failing height, now changed to 2400 this morning. Ram is 4gb with 1gb swap.

Thanks for looking into this. It shouldn’t be offline, I’ve just checked and it has been online for quite a while. You probably not being able to see the chain height might indicate the reason why it’s failing on chain height.